Lands' End. Macy's online. JCPenny.

Don't forget ebay. :)

Sometimes, you can get great stuff that's simply discontinued.

Target usually has cute things. My boys have quilts and shams from PBK and Company Kids, but I use plain white sheets for all the beds in our house. Perhaps that would help keep the cost down.

Ikea has some cute kids bedding and very reasonably priced.

My girls have pbk quilts with target sheets. Before that, they had sets from eBay. My son has a land of nod quilt I got from Craigslist, and his sheets are tommy hilfiger and company kids.

Many of my kids' favorite items came from home goods. We live in snow country, and they love the fleece sheets which start appearing in our stores around October.

Otherwise we have bought from PBK (But they say the quilts are too heavy and don't like them), JCP, and Company Kids.

i found some nice flannel kid's bedding at kohls.com.

you can also try thecompanystore kids. their linens are pretty high quality.

My son's PBK quilt held up incredibly well. After 7 years (ages 2-9) it still looked great, even though it had been through just about everything, stomach bugs, nighttime accidents, etc. We updated his room recently and I bought a target quilt that I already regret. The PBK was so much better. I'd go with target sheets and PBK quilt. You can sometime find discounts on eBay for new PBK items or if you're near an outlet, try there.

Pine Cone hill has lovely bedding for children and when on sale it is not too bad. If you like Pottery Barn Kids they reduce that stuff regularly by 50% at the end of each season.

Land of Nod, Serena and Lily, Nandini.

I just bought some duvet covers at H&M for super cheap. They are surprisingly good quality and feel actually very smooth and soft. DD has a whole bunch of duvet covers to easily change the look of your room.

Look at etsy. DD2 just bought adorable organic toddler bedding for DGS from an etsy shop.

Craigslist or eBay.

My daughter's 1st was PBK but recently we updated her girls pinks with a different color scheme. She confided that she hated her quilt (crazy quilt pattern with lots of embroidery). We purchased cheap Target comforter and sheet sets. She loves her new bedding! I cringed, but DH said we'll just try it. She still keeps the quilt for a cool night top cover.
My son's is a Ralph Lauren down alternative comforter set I scored at TJMaxx.
We have a PB outlet in an hours drive. See if there's one near you, then call to see when the beddings on sale if you fell in love with something.

Hanna Anderson just opened their home section for children yesterday. No crib or toddler bedding. Similar style as Serena & Lily.

From ebay...